Toxicology Commons^™

Mechanisms Of Thymic Toxicity Induced By Environmentally Relevant Concentrations Of Arsenic, Huan Xu

Biomedical Sciences ETDs

Arsenic, a ubiquitous environmental contaminant, is known to cause immunotoxicity. However, the mechanisms of arsenic induced immunotoxicity are still not clear. Arsenite (As⁺³), the trivalent inorganic form of arsenic, was found to increase DNA damage and inhibit PARP activity in thymus cells at 50 nM in vitro. Oxidative stress and double strand breaks (DSBs) formation occurred in thymus cells exposed to As⁺³ at 500 nM. The genotoxicity was found to be related to As⁺³ exporter expressions and reversed by zinc supplement. IL-7 signaling, the critical cytokine signal for the early DN thymic T cell proliferation, …